Sound radiation measurement with nearfield holography
نویسندگان
چکیده
منابع مشابه
A general radiation model for sound fields and nearfield acoustical holography in wedge propagation spaces.
In this work an expression for the solution of the Helmholtz equation for wedge spaces is derived. Such propagation spaces represent scenarios for many acoustical problems where a free field assumption is not eligible. The proposed sound field model is derived from the general solution of the wave equation in cylindrical coordinates, using sets of orthonormal basis functions. The latter are mod...
متن کاملOn nearfield acoustic holography
Such functions u are called radiating solutions. Pressure measurements are taken by acoustical sensors located in a domain Ω0 inside or outside the cabin or on a surface Γ0 = ∂Ω0 . Our goal is to reconstruct u inside Ω, or the normal velocity v = ∂νu on Γ = ∂Ω, (ν is the unit exterior normal to ∂Ω). This is a mathematical model of the nearfield acoustic holography [W], [Wu]. H(m)(Ω) denotes the...
متن کاملLow-Frequency Loudspeaker Assessment by Nearfield Sound-Pressure Measurement*
GLOSSARY OF SYMBOLS r distance from pressure sample point to center of piston a radius of circular radiator R_ dc resistance of driver voice coil ao radius of diaphragm, = _/SD/_r E surface area ay radius of circular vent, = 5/Sv/_r SD effective projected surface area of driver diaphragm c velocity of sound in air, = 343 m/s Sv cross-sectional area of vent ein voltage applied to driver input SP...
متن کاملPartial Sound Field Decomposition in Multi-Reference Nearfield Acoustical Holography by Using Optimally-Located Virtual References
Multi-reference nearfield acoustical holography can be used to decompose the sound field radiated by a composite source into individual partial sound fields. To obtain physically meaningful partial fields, i.e., fields closely related to particular component sources, the reference microphones should be positioned as close as possible to the component sources. However, it is not always possible ...
متن کاملDevelopment of an Energy-Based Nearfield Acoustic Holography Technique
Acoustical-based imaging techniques have found merit in determining the behavior of vibrating structures. These techniques are commonly used in numerous applications to obtain detailed noise source information and energy distributions on source surfaces. This work focuses on the continued development of the nearfield acoustical holography (NAH) approach. Source reconstructions using NAH are rel...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: The Journal of the Acoustical Society of America
سال: 1982
ISSN: 0001-4966
DOI: 10.1121/1.2019988